Bill Ackman

William Albert Ackman was born on May 11, 1966, in Chappaqua, New York, to Lawrence David Ackman (former chairman of Ackman-Ziff Real Estate Group) and Ronnie I. Posner.⁠[2]

Ackman grew up in Chappaqua, New York, where his father worked in commercial real estate finance. He attended and graduated from Horace Greeley High School, a local public school, and then went on to Harvard UniversityHarvard UniversityHarvard University is a private research university in Massachusetts, established by the Massachusetts Bay Colony legislature in 1636 and named in 1639 for early benefactor John Harvard. Its principal campuses are in Cambridge and the Allston and Longwood neighborhoods of Boston. It includes Harvard College, graduate and professional schools, and the Radcliffe Institute for Advanced Study. Two governing boards share oversight. Alan M. Garber was president as of October 2026, and the endowment stood at $56.9 billion at the end of fiscal 2025.Open the full entry.⁠[3]

In 1988, Ackman graduated from Harvard College with a Bachelor of Arts degree, magna cum laude. He rowed on the men’s crew team as an undergraduate and later supported Harvard’s rowing program.⁠[4][1]

After college, Ackman worked at Ackman Brothers & Singer, a real estate investment bank connected to his family. As he later recalled in an interview, the job mainly involved arranging real estate financing for clients, and he gradually wanted to move from providing deal services to making investment decisions himself. Leonard Marx, an investor his father introduced him to, recommended that he read Benjamin Graham’s The Intelligent Investor, which influenced his later choice of an investing career.⁠[5][6]

In 1992, Ackman received an MBA from Harvard Business School and then founded Gotham Partners, beginning to manage investment capital. Pershing Square’s official biography lists his role there as co-founder and co-manager, a tenure that lasted until 2003.⁠[7][5][1]

In its later years, Gotham Partners faced liquidity and investor redemption pressures and ultimately wound down its operations. During this period it took part in the contest to acquire Rockefeller Center but did not gain control. Ackman subsequently reorganized his investment management business.⁠[3]

In December 2003, Pershing Square Capital ManagementPershing Square Capital ManagementPershing Square Capital Management is an American investment management firm founded by Bill Ackman and headquartered in New York. It pursues an active investment strategy of concentrated, long-term holdings with engagement in the governance of portfolio companies, and mainly manages permanent capital funds such as the London-listed Pershing Square Holdings. In April 2026, its parent company, Pershing Square Inc., went public on the New York Stock Exchange.Open the full entry was formally established as an investment adviser; in January 2004, Pershing Square, L.P. began investing. The firm’s name comes from the Pershing Square area on 42nd Street in New York, where its early office was located. The founding of the management firm and the launch of the fund therefore correspond to 2003 and 2004, respectively.⁠[8]

In December 2006, Bill Ackman and Karen Ackman co-founded the Pershing Square Foundation. The foundation uses grants and social investments to support education, health care, social services, and scientific research; it is a separate organization from Pershing Square, the financial firm that manages client investment assets.⁠[9][10]

During the 2007–2009 financial crisis, Ackman’s public bearish investment against the bond insurer MBIA drew attention. He later explained in an interview that the trade used credit default swaps to gain potential returns from a deterioration in credit risk with a limited initial outlay, a risk structure different from directly borrowing shares to sell short.⁠[11][12]

According to Ackman’s recollection in a 2024 interview, Pershing Square began investing in the mall owner General Growth Properties in November 2008. He judged that the company’s property values still exceeded its liabilities and that its main difficulty was the inability to refinance short-term debt during the financial crisis, and he then helped push for a bankruptcy reorganization that preserved shareholder equity.⁠[12]

He regards the episode as a long-term investment rather than a short-term trade, and noted that the team continued to hold businesses later spun off from General Growth.⁠[12]

Ackman pushed the retailer Target to restructure its credit card business and its real estate holdings. In 2009, he launched a proxy contest for board seats but was not elected, and the related concentrated investment vehicle suffered major losses. By 2011, Pershing Square had sold its Target shares.⁠[13]

In October 2010, Ackman disclosed an investment in J.C. Penney. He subsequently joined the board, and in 2011 he pushed for Ron Johnson, a former head of Apple’s retail business, to become CEO, hoping to transform the department store’s operations and image. The overhaul failed to deliver the expected growth in customers and became a major setback in his career.⁠[13]

In 2012, Ackman joined the board of Canadian Pacific Railway and pushed for the appointment of new directors and of Hunter Harrison, former CEO of Canadian National Railway. He subsequently served on the company’s finance, corporate governance, and nominating committees. This is a representative case of his use of shareholder activism to bring about a change in management.⁠[14]

In December 2012, Ackman publicly questioned Herbalife’s business model and built a short position of about $1 billion. He argued that the company’s distribution system amounted to a pyramid scheme; this was his investment thesis and public allegation, not a court ruling against the company at the time.⁠[15]

On August 13, 2013, Ackman resigned from the J.C. Penney board. The failure of Ron Johnson’s overhaul and disagreements within the board over subsequent leadership made it difficult for him to continue pursuing his original plan.⁠[13]

After he left the board, Pershing Square sold about 39.08 million J.C. Penney shares to Citigroup. ForbesForbesForbes is an American business media brand that began with Forbes magazine, founded by B.C. Forbes in 1917. It is known for rankings such as the Forbes 400, the World’s Billionaires list and 30 Under 30, and operates Forbes.com, ForbesLive events and licensed editions in 81 countries. Since 2014 a majority stake has been held by the Hong Kong investment group Integrated Whale Media; a 2021 plan to list on the New York Stock Exchange through a special purpose acquisition company was terminated in 2022. It is headquartered in Jersey City, New Jersey.Open the full entry, updating its report based on a regulatory filing disclosed on August 28, reported that the fund actually sold the shares to Citigroup at $12.60 per share, receiving about $492 million, for a final investment loss of nearly $500 million; Citigroup resold the shares to the public at $12.90.⁠[16]

On September 23, 2013, the Pershing Square Foundation announced its support for the Oxford Pershing Square Graduate Scholars Programme with a £4.5 million gift, matched by £3 million from the University of Oxford. The first scholars enrolled in the fall of 2014, and the program combines a specialized master’s degree with an MBA.⁠[9]

In 2014, Harvard announced gifts associated with the Ackman family: $17 million for research on human behavior, including professorships and research funds, and another $9 million supporting global health and the men’s rowing program.⁠[4]

In October 2014, Pershing Square Holdings (PSH), a closed-ended investment company, listed on Euronext Amsterdam. In May 2017, the company also listed on the London Stock Exchange. PSH is the investment vehicle, while Pershing Square Capital Management is responsible for managing its assets.⁠[8]

In 2015, Pershing Square began investing in the pharmaceutical company Valeant. The company was subsequently hit by controversy over drug pricing and its business model, as well as regulatory scrutiny, and its share price fell sharply; Ackman later joined its board and took part in handling the crisis.⁠[17][18]

On April 27, 2016, Ackman, as CEO of Pershing Square and a director of Valeant, appeared at a hearing of the U.S. Senate Special Committee on Aging on Valeant’s business model and its impact on patients and the health care system. Those appearing also included J. Michael Pearson and Howard Schiller.⁠[18]

On July 15, 2016, the U.S. Federal Trade Commission announced that Herbalife had agreed to pay $200 million in consumer redress and to restructure its U.S. multilevel marketing business so that compensation is tied to verifiable retail demand rather than simply to recruiting distributors. This regulatory settlement did not mean that Ackman’s investment had become profitable.⁠[19]

In August 2016, Pershing Square sold its remaining Canadian Pacific shares; in September of that year, Ackman left the board, ending a directorship that began in 2012.⁠[14]

On March 13, 2017, Pershing Square sold its remaining Valeant stake. ReutersReutersReuters is an international news agency founded in London in 1851 by Paul Julius Reuter and is now the news business of Thomson Reuters. It provides text, photo, video, and graphics coverage to media and institutional clients and distributes it through channels such as Reuters Connect.Open the full entry reported the next day that the investment lost more than $3 billion in total; this was a fund investment loss, not a loss in Ackman’s personal account. Pershing Square said the exit would realize a tax loss and allow it to focus on other investments.⁠[17]

On November 7, 2017, Ackman lost a contest for board seats at ADP’s annual shareholder meeting. The three candidates he backed, including himself, received less than a quarter of the votes. The two sides had previously argued publicly over operating efficiency, technology products, and management performance, and ADP’s management opposed his reform proposals.⁠[11]

On December 29, 2017, Pershing Square announced an agreement in principle with Valeant to settle two investor lawsuits related to the 2014 bid for Allergan for a total of $290 million, of which Pershing Square would pay $193.75 million. The dispute concerned purchases of securities before the acquisition plan was announced; Pershing Square denied that the lawsuits had merit.⁠[20]

On February 28, 2018, Ackman confirmed that he had ended his bearish bet on Herbalife. In 2017, he had converted the direct short position into put options. The long public battle did not end with the share price going to zero as he had predicted, and Reuters did not at the time confirm the final loss on the trade.⁠[15]

According to the Stanford Securities Class Action Clearinghouse, the settlement agreement in the Allergan derivative securities investor case was signed in January 2018 and received final court approval, with a final judgment, on August 13. In January 2020, the court then approved the distribution of the settlement fund.⁠[21]

In March 2020, Pershing Square used credit index protection to hedge against the impact of the pandemic and closed the trade on March 23. The firm’s March 25 letter to investors said the hedges generated about $2.6 billion in proceeds for its funds, against $27 million in related premiums and costs, of which about $2.1 billion was attributable to PSH.⁠[22]

Ackman said the hedging gains offset part of the decline in the equity portfolio and were used to add to or buy back positions in several public companies.⁠[22]

On January 26, 2022, Ackman disclosed to investors that Pershing Square had bought more than 3.1 million Netflix shares over the preceding several trading days. He described the share price decline at the time as an opportunity to build a long-term position and mentioned using part of the proceeds from ending an interest rate hedge to increase equity investments.⁠[23]

On April 20, 2022, Ackman announced the sale of the entire Netflix position. He explained in his letter that changes in subscribers and in the business model had increased the uncertainty of long-term forecasts; the investment reduced the fund’s year-to-date return by about four percentage points.⁠[24]

In November 2022, Ackman discussed on social media his personal investments in TRM Labs, TaxBit, ORIGYN, and several crypto-related funds, saying the related allocations amounted in total to less than 2% of his personal assets. He described participating in such projects as a way of learning about new technology.⁠[25]

He had cited Helium as an example of a blockchain application; after this drew controversy, he clarified that the posts were not meant to encourage others to invest and that actual demand was not yet sufficient to support the token’s valuation at the time.⁠[25]

On September 29, 2023, Pershing Square SPARC Holdings, of which Ackman is chairman and CEO, disclosed its first distribution of special purpose acquisition rights. The company said the distribution itself did not collect money from investors, and that capital would be raised later, after a definitive business combination agreement was signed and offering materials were provided.⁠[1][26]

In June 2024, Pershing Square sold a 10% stake in its management company to strategic investors; Ackman has served as chairman of Pershing Square Inc. since that month. The transaction involved equity in the asset management business, not a sale of the funds’ entire investment portfolios.⁠[8][1]

On July 13, 2024, Ackman publicly endorsed Donald Trump in the U.S. presidential election. Reuters noted at the same time that he had called on Trump to resign after the January 6, 2021, attack on the Capitol, reflecting a shift in his public political stance.⁠[27]

On July 31, 2024, Pershing Square USA announced the withdrawal of its initial public offering plan at the time. Ackman said in a statement that prospective investors were concerned about whether they should wait until after the listing to buy, so the team decided to reassess the offering structure. This withdrawal and the offering completed later in 2026 belong to different stages.⁠[28][29]

On May 5, 2025, Pershing Square completed a $900 million investment in Howard Hughes Holdings, subscribing for 9 million new shares and raising its economic interest to about 46.9%. Ackman became executive chairman, Ryan Israel became chief investment officer, and David O’Reilly remained CEO.⁠[30]

The two sides aim to turn Howard Hughes from a primarily real estate company into a holding company with diversified businesses. The transaction caps Pershing Square’s maximum ownership at 47% and its voting power at 40%.⁠[30]

On April 30, 2026, Pershing Square announced the completion of the $5 billion initial public offering of Pershing Square USA. The transaction was carried out together with the listing of Pershing Square Inc., the parent of the management company: the former is an investment fund, and the latter is the listed entity of the investment management business.⁠[29]

As of May 31, 2026: Pershing Square Holdings (PSH) AUM $17,826.6M; total core strategy AUM $24,235.2M; firm-wide (including Howard Hughes) $33,803.8M.⁠[31]

On May 29, 2026, the board of Universal Music Group rejected the takeover proposal Pershing Square submitted on April 7, saying it undervalued the company and was not in the best interests of its stakeholders. This was a rejected takeover proposal, not a completed acquisition.⁠[32]

On June 4, Cinco Días reported that Ackman’s investment firm had sold its Universal Music stake, with Universal Music repurchasing part of the shares. This follow-up meant that his earlier long-term investment and proposed full takeover did not continue as originally planned.⁠[33]

Moneywise reported on June 1, 2026, on his School of Hard KnocksSchool of Hard KnocksSchool of Hard Knocks is a business-interview media brand founded in 2021 by James Dumoulin, Jack Dumoulin and Joshua Smith, based in Austin, Texas. Its street interviews, long-form videos and podcast explore guests’ careers and business experiences. It also operates content services and the School of Mentors community.Open the full entry interview with James DumoulinJames DumoulinJames Dumoulin is a cofounder, interviewer and speaker at School of Hard Knocks, a media brand focused on entrepreneurship and business experience. He works with his brother Jack Dumoulin and cofounder Joshua Smith.Open the full entry. He encouraged young entrepreneurs to keep learning, develop valuable ideas and persist through rejection, and recommended learning artificial intelligence tools and coding.⁠[34]

On June 17, the channel published Asking Billionaires What To Invest In!, a compilation including his interview at a Beverly HillsBeverly HillsBeverly Hills is an incorporated city in Los Angeles County, California, known for its film-industry residents, Rodeo Drive shopping district and hotels. Incorporated on January 28, 1914, it covers about 5.71 square miles and recorded 32,701 residents in the 2020 census. It operates under a council–manager system. The Metro D Line extension reached Wilshire/La Cienega in May 2026.Open the full entry business conference. Original video: https://www.youtube.com/watch?v=Z7aS-7Mw_Wg (opens in a new window).⁠[35]

Pershing Square’s second-quarter 2026 shareholder letter disclosed that it had reinvested in Netflix and added new positions including Visa, Mastercard, S&P Global, Intercontinental ExchangeICEICE (Intercontinental Exchange) is a US financial-market infrastructure company founded in 2000. It operates exchanges and clearing services, fixed-income and data businesses, and mortgage technology. Its businesses include the New York Stock Exchange; founder Jeffrey Sprecher is chair and CEO.Open the full entry, and Alcon. Ackman and Ryan Israel each explained their reasoning for these investments in the letter; these are the management team’s views and do not constitute assured returns.⁠[36]

The same letter announced the start of preparations for Pershing Square Ventures, which is intended to invest in private growth companies through an evergreen, permanent capital structure and may continue to hold companies after they go public. The initial portfolio is planned to include some private investments already made by the management company and some investments of the Ackman family office; as of the letter’s publication, it was still in preparation.⁠[36]

In August 2026, Ackman and his wife, Neri Oxman, announced the Ackman Oxman Institute, focused on brain science, neurorehabilitation, and related medical technology. The American Bazaar reported on August 20 that the two pledged stock worth about $400 million to support the nonprofit and planned to build a research facility in New York. That figure is the value of the shares at the time described, not a fixed cash donation.⁠[37]

On September 8, 2026, The Holy Grail of Investing, a podcast hosted by Tony RobbinsTony RobbinsTony Robbins is an American author, speaker, entrepreneur and personal-development coach born on February 29, 1960. He founded Robbins Research International and the Tony Robbins Foundation. Known for large seminars and books including Unlimited Power, Awaken the Giant Within and MONEY: Master the Game, he is also involved in investing, health services and philanthropy.Open the full entry and Christopher Zook, premiered an interview with Ackman covering contrarian investing, black swan hedging, and lessons from 22 years of concentrated investing at Pershing Square.⁠[38][38][38][39]

Ackman said on the show that two forces in the market had changed fundamentally compared with 10 or even 20 years earlier. The first was indexation: as more people turned to index investing, he said that a quarter of every American business, “plus or minus,” was owned by some combination of Vanguard, State StreetState StreetState Street Corporation is a Boston-based US financial services group serving institutional investors through investment servicing, investment management and market services. Its businesses include custody, fund accounting and administration, investment software and SPDR funds. It trades on the New York Stock Exchange as STT.Open the full entry, and Northern TrustNorthern TrustNorthern Trust (Northern Trust Corporation) is a financial holding company headquartered in Chicago whose principal subsidiary, The Northern Trust Company, was founded by Byron L. Smith in 1889. Focused on asset servicing, wealth management, asset management and banking for institutions, families and high-net-worth individuals, it is one of the world’s major custody banks.Open the full entry, which effectively took float out of the market; with a smaller float, the marginal buyer and seller had more impact on the stock price, and today’s marginal buyers and sellers were firms like Citadel and Millennium that used large amounts of leverage, had very large gross books, and were increasingly short-term. The second was retail investors, who he said had become even more speculative with one-day options.⁠[39][39][39][39][39]

He argued that these forces led to huge volatility, citing IBM, whose stock fell 25% after it disappointed investors, as a big move for a relatively large company. He said that when he first entered the business he could think of only one example of a big company’s stock dropping by a similar amount, when Philip Morris fell 20% after losing its first big tobacco litigation, whereas now some relatively large company’s stock moved enormously almost every quarter.⁠[39][39][39]

Ackman said that a stock could drop 25% overnight with no liquidity in between, which made a stable long-term capital base important; most investors, he said, were short-term focused because of how they were compensated or how their risk was managed, and would buy only if they were confident the stock would be higher on December 31, which he argued created opportunities for investors who could take a long-term view to buy high-quality businesses.⁠[39][39][39][39]

An investigative report by CNNCNNCNN (Cable News Network) is an Atlanta-based news organization founded by Ted Turner on June 1, 1980, as the world’s first 24-hour television news channel. It has been owned in turn by Turner Broadcasting System, Time Warner, AT&T and Warner Bros. Discovery, became part of Skydance Corporation along with Warner Bros. Discovery in October 2026, and is one of the five networks that rotate in the White House television pool.Open the full entry said that Jared KushnerJared KushnerJared Kushner (Jared Corey Kushner) is an American businessman, investor and political figure, and the founder and chief executive officer of the private investment firm Affinity Partners. He ran his family’s real estate business, Kushner Companies, and bought The New York Observer; from 2017 to 2021 he was a senior adviser in the White House to his father-in-law, Donald Trump, and helped bring about the Abraham Accords. From 2025 he took part in Gaza ceasefire negotiations as an unpaid volunteer, and in February 2026 Trump announced him as an envoy of peace. Potential conflicts of interest between his Gulf sovereign-wealth-fund backing and his diplomatic role have been investigated by congressional Democrats and the media; he and the White House deny them.Open the full entry’s investment firm, Affinity PartnersAffinity PartnersAffinity Partners is a private investment firm founded in 2021 and wholly owned by Jared Kushner, based in the Miami area of Florida and funded mainly by foreign investors including sovereign wealth funds of Saudi Arabia, Qatar and the United Arab Emirates; its registered investment adviser entity is A Fin Management LLC. As of March 2026 it reported about $6.16 billion in assets under management, and one of its largest publicly known holdings is the Israeli financial group Phoenix Financial. Because its founder also takes part in U.S. government diplomacy in the Middle East, its foreign funding and fee structure have repeatedly been investigated by congressional Democrats; the firm denies any wrongdoing.Open the full entry, was the largest shareholder of the Israeli financial institution Phoenix FinancialPhoenix FinancialPhoenix Financial (Phoenix Financial Ltd., formerly The Phoenix Holdings) is an Israeli listed financial services group traded on the Tel Aviv Stock Exchange, operating insurance and asset management businesses, with about NIS 658 billion (roughly $217–220 billion) in assets under management as of June 30, 2026. Jared Kushner’s Affinity Partners has been its largest shareholder since January 2025; in October 2026 CNN reported on Israeli military-linked holdings in its portfolio, prompting controversy over Kushner’s potential conflicts of interest.Open the full entry, and Kushner then said on X that the report’s headline was “deeply misleading.” On October 2, 2026, Ackman defended Kushner on X, calling him “a first-class human being,” saying the United States was “extremely fortunate” to have him representing the country’s interests in negotiations for peace, hostage return, and otherwise, and calling it “pathetic” that people attempted to take down others out of spite, envy, political calculation, or otherwise.⁠[40][40][40][41][41][41]

On October 6, 2026, The Modern Investor, a podcast from the financial media company Finimize, released an interview with Ackman conducted by Finimize CEO Carl Hazeley. Ackman likened the global competition to develop artificial intelligence to developing a nuclear weapon: the technology could bring many benefits to mankind but also had the potential to destroy it; he said that before nuclear weapons were tested people could at least rely on their understanding of physics, whereas humanity’s understanding of the human brain was limited.⁠[42][42][42][42][42]

On the show he attributed rising market volatility to two principal forces: first, indexation, as index funds, which are in effect permanent owners, held an ever-greater share of companies, giving the marginal buyer and seller more impact on price; and second, firms such as Citadel, Millennium, and Jane Street whose leveraged strategies are oriented toward very short-term trading, so that stock prices moved sharply when a company disappointed or exceeded expectations. He said this had given Pershing Square the opportunity to own some truly great companies at occasionally very cheap prices, noting that the firm manages public entities and has so-called permanent capital.⁠[42][42][42][42][42][42][42][42]

The Pershing Square Foundation has since supported cancer and neuroscience research, including the MIND program launched in 2022 and an ovarian cancer research program in 2025. In 2024, Pershing Square Philanthropies became the brand that brings this charitable work together. Ackman and Neri Oxman serve as co-trustees on its public leadership team.⁠[10][5]

Pershing Square: Founder and CEO; Official website: https://www.pershingsquareinc.com/ (opens in a new window); Official biography: https://www.pershingsquareinc.com/team/bill-ackman/ (opens in a new window).⁠[1]

Pershing Square Holdings: Listed investment company managed by his investment management team; Official website: https://pershingsquareholdings.com/ (opens in a new window).⁠[29]

Pershing Square Foundation / Pershing Square Philanthropies: Co-founder and charitable trustee; Official website: https://pershingsquarephilanthropies.org/ (opens in a new window).⁠[5][10]

Howard Hughes Holdings: Executive chairman since May 2025; Investor relations website: https://investor.howardhughes.com/ (opens in a new window).⁠[30]

Harvard College: Undergraduate alma mater; Harvard University website: https://www.harvard.edu/ (opens in a new window).⁠[4]

Harvard Business School: MBA, 1992; Official website: https://www.hbs.edu/ (opens in a new window).⁠[7]

X: Public account: @BillAckman, https://x.com/BillAckman (opens in a new window).⁠[43]

Pershing Square SPARC Holdings: Chairman and CEO; Official website: https://pershingsquaresparcholdings.com/ (opens in a new window).⁠[1][44]

Pershing Square: Official website: https://www.pershingsquareinc.com/ (opens in a new window)⁠[1]

Pershing Square Holdings: Official website: https://pershingsquareholdings.com/ (opens in a new window)⁠[29]

Pershing Square Foundation: Official website: https://pershingsquarephilanthropies.org/ (opens in a new window)⁠[5]

Howard Hughes Holdings: Official website: https://investor.howardhughes.com/ (opens in a new window)⁠[30]

Pershing Square SPARC Holdings: Official website: https://pershingsquaresparcholdings.com/ (opens in a new window)⁠[44]